The present invention relates to curtain antennae including a rotary support supporting at least one vertical curtain of doublets and a reflecting part. This reflecting part is made of wires and is disposed behind the curtain or curtains, that is to say, in the case of two curtains, between the curtains.
Such antennae are known and are used for example for decametric wave operation; they very often have only a single supply line which generally passes through the support and, in the case of two curtains, supplies one or other of the two curtains through a switching device.
The azimuth aiming angle of these known antennae is readily adjustable, in any direction, by rotating the mast. On the other hand, these antennae are not adjustable in elevation for known solutions modifying the elevational angle of a fixed curtain antenna are practically unusable in rotary antennae. In fact, they would require feeding the full wave doublets of a curtain in groups of doublets, using as many lines as there are groups, so as to be able to disconnect the part of the doublets of the curtain through switching, matching, and symmetrization assemblies placed at the foot of the antenna. Now, it is already difficult to form a single feed line capable of rotating by + and -180.degree. from a rest position and the problem becomes impossible to solve if it is a question of several lines to be rotated through 180.degree., without forgetting that in addition a low standing wave ratio must be obtained at the input of the antenna.